Abstract
Porotrichum saotomense Enroth & Shevock (Neckeraceae) is described as a new species from the Republic of São Tomé & Príncipe. It is morphologically closest to P. quintasii Broth., differing primarily in the non-complanate and nearly symmetric leaves, much stronger, spinose costa, longer seta and longer exostome teeth and endostome processes. Other additions to the moss flora of São Tomé & Príncipe are Homaliodendron piniforme (Brid.) Enroth, Calyptothecium acutifolium (Brid.) Broth. var. breviusculum (Müll. Hal.) Argent, and Symphyodon pygmaeus (Broth.) S. He & Snider. Neckeropsis disticha (Hedw.) Kindb. is new to the island of São Tomé.